Lock construction



Sept. 10, 1935. H F. KEIL .Y 2,014,233

LOCK CONSTRUCTION INVENTOR ATTORN EYS Sept. 10, 1935. 4 H. F, KElL2,014,233

LOCK CONSTRUCTION Filed June 26, 1934 l 2 Sheets-Sheet 2 INVENTOR BYHenKeL'Z m *QH/Mz ATTORN EYS Patented Sept. 10, 1935 PATENTT'OFFICE LOCKCONSTRUCTION Henry F. Keil, Scarsdale, N. Y., assigner to Francis Keil &Son, Inc., a corperation of New York Application June 26, 1934, SerialNo. 732,451

33 Claims.

This invention relates to lock construction and more particularly to akey-controlled mechanism of the so-called cylinder type.

One of the objects of this invention is to pro- Vide a simple,inexpensive, and reliable lock construction of the. above-mentionedcharacter and more particularly one that may be quickly and easilyassembled, in the course of manufacture or which may be with facilityand convenience disassembled for purposes of replacement, repair, orchange of the parts or their relation and then reassembled. Anotherobject is to provide a construction of the above-mentioned characterthat will be compact, inexpensive to manufacture, simple to operate, andthat will be also foolproof. Another object is to provide a lockconstruction which is armored against drilling, or the like, in asimple, inexpensive and compact manner, and, moreover, without creatingunsightliness of appearance. Another object is to provide a simple,inexpensive and practical connection between the key plug and operatingbar and also to provide such a connection that is well adapted to meetvarying conditions of practical use. Other objects will be in partobvious or in part pointed out hereinafter.

The invention accordingly consists in the features of construction,combinations of elements, and arrangements of parts as will beexemplified in the structure to be hereinafter described and the scopeof the application of which will be indicated in the following claims.

In the accompanying drawings in which are shown several of the variouspossible embodiments of my invention,

Figure l is a vertical central sectional view through the lock mechanismas it appears when installed in a door, or the like;

Figure 2 is a transverse sectional View, as seen along the line 2-2 ofFigure 1;

Figure 3 is a plan view, as seen from the top in Figure 1, of the casingper se as the latter appears disassembled from the other parts shown inFigure 1;

Figure fi is an end View, as seen from the lefthand end of Figure 1,more particularly as seen along the line li--li of Figure 1;

Figure 5 is a plan View of the connecting bar;

Figure 6 is a sectional view, as seen along the line 'ii-5 of Figure 5,showing more clearly certain details of construction of the connectingbar;

Figure '7 is a detached side elevation showing the inner relation of theconnecting bar with the key plug;

Figure 8 is a fragmentary central vertical sectional View, as seensubstantially along the line 3 3 of Figure 4.-;

Figure 9 is a top plan view of a modified form of mechanism;

(Cl. 'Y0-47) Figure 10 is a front elevation thereof, as seen from thebottom in Figure 9;

Figure 1 is an end view, as seen from the left in Figure 9;

Figure 12 is a detached side elevation showing the interconnectionbetween the connecting bar and the key plug;

Figure 13 is a plan view of the connecting bar;

Figure 14 is a sectional view of the connecting bar, as seen along theline I4-I4 of Figure 13, and

Figure 15 is a plan view of a member coacting to maintain the connectionbetween connecting bar and related parts.

Similar reference characters refer to similar parts throughout theseveral views in the drawings.

Referring now tc the drawings and more particularly to Figure 1, I havethere shown my lock construction as it might be applied to a door, orthe like, for actuating, under the control of a suitable key, a bolt orlatch mechanism I@ suitably mounted upon the door II, as upon the insideor left-hand face thereof, the key-controlled or lock mechanism beingmounted in a hole I2 in the door I I, ina manner more clearly describedhereinafter.

The lock mechanism includes a casing generally indicated at I3 suitablyshaped, as bycasting, or the like, to provide a front or escutcheonplate I4, preferably circular (see Figure 2) from the rear or left-handside of which, as seen in Figures 1 and 3, extends a cylinder-likehousing portion I5 along the top of which extends a tumbler housingportion I6 (see also Figure e). The casing I3 is bored out through thecylinder portion I5 thereof, as at Il, in order rotatably to receive andmount the cylindrical key plug I8 whose forward or right-hand end (seeFigure i) is of larger diameter formed as by the spaced peripheralshoulders I8-2, the latter having therebetween an annular groove ZI, thecasing I3 being counterbored as at 22 to a larger diameter than thediameter of the bore I1 in order thus to accommodate the largerdiametered portion ISB- of the key plug I8; this counterbore 22 ispreferably accommodated within the thickness of the front plate le, thelatter being made of suitable thickness for that purpose,

With the key plug I8 inserted into the bore and thus positioned as seenin Figure 1, the annular or ring-shaped shoulder I9 of the key plug Iiifits into the angle of the counterbore 22 and thus limits movement ofthe key plug I8 in a direction toward the left, as viewed in Figure 1,and in that position of the parts, the left or rear end of the key plugI8 is preferably flush with the left-hand end of the cylindrical housingportion I5, as better appears in Figure 1.

p The key plug I S is provided with a suitably shaped key slot 23extending lengthwise thereof .and preferably throughout the lower halfportion thereof (see also Figure 2) and a suitably crosssectioned keymay thus be inserted into the key slot 23, the key being ysuitablyserrated, notched or edged to coact with and control suitable tumblerdevices which coact with the casing I3 to prevent or to permit rotationof the key plug I8? relative to the casing I3. In so far as certainfeatures of my invention are concerned, these tumbler devices may takeany suitable orlappropriate form and number and illustratlvely andpreferably they are in the form of so-called pin` tumblers, as shown inFigure 1 and illustratively there are five sets.

Accordingly, the key plug I8 is provided with tumbler-receiving recesses3I, 32, 33, 34 and 35, these being generally cylindrical and extendingfrom the upper face of the key plug I8 (with the latter in the positionshown in Figures l and 2) down intov communication with the key slot 23in order thereby to expose to the latter and to a key inserted thereinthe pin tumblers 4I, 42, 43, lill and t5 respectively received in theaforesaid recesses.

These tumbler pins are of suitably differing lengths, as is understoodin the art, so that, when the proper key is inserted into the key slot23, these tumbler pins ,are lifted (as viewed in Figure l) to bringtheir upper faces or edges substantially exactly to the periphery of thekey plug i8 itself, thereby ejecting from the tumbler-receiving recessesin the key plug I8 the coacting pin tumblers 5I, 52, 53, 54 and 55 whichtheretofore had projected from the tumbler-receiving housing portion I6of the casing I3 into the key plug recesses, thereby precluding rotationof the key plug.

These tumbler pins 5I, 52, 53, etc. are slidably mounted intumbler-receiving recesses 6I, 62, 63, 64 and 65, respectively, thelatter being formed as by casting or drilling, in the housing portionI6, opening at their lower ends into the bore I1. These tumblers arespring-pressed downwardly by springs 1I, 12, 13, 14 and 15,respectively, the springs being interposed between the tumblers and theupper closing wall of the tumbler-receiving recesses; this` closing wallmay be in the form of a plate 24 extending along the top of the housingportion IS between flanges I6a and I6b (Figure 4) of the latter, theseflanges being burred or pressed over to hold the plate 24 in place. l

The tumbler-receiving recesses 3l, 32, etc. in the key plug I 8 and thetumbler-receiving recesses Si, @2, etc. in the casing I3 larerespectively alined when the key plug I8 has its ring-like shoulder orflange I9 bottoming in the counterbore 22 (Figure l) and this alinementis maintained by a plate member 25 (Figures l and 2) that is receivedwithin the ange I4 and that coacts with the annular groove 2I of the keyplug I8.'

Not only is such alinement of the respective tumbler-receiving recessesand tumblers in the casing and key plug achieved and maintained butalso, as later pointed out hereinafter, the resultant fixing of theaxial position of the key plug il relative to the casing I3 and moreparticularly relative to the bored-out cylinder portion I5 thereof ismade to coact in controlling and maintaining the interconnection, at therear or lefthand end of the key plug I8 of the connecting or operatingbar 28 which extends into the bolt mechanism Iii; this unique coactionmay be achieved by illustrative constructions and arrangements as arehereinafter described in greater detail and according to which theinterconnection between key plug and connecting bar may not only bereliably maintained but may also be shiftable or capable of quick andeasy rearrangement tomeet certain of the varying conditions of practicaluse pointed out hereinafter. The above-mentioned plate member 25 may,furthermore, andin accordance with such coacting features of myinvention, be made to maintain assembly of key plug with respect to thecasing while the above-mentioned interconnection is changed or shiftedeven though the member 25 otherwise aids in maintaining disconnection ofthe connecting bar from the key plug, thus preventing spilling of,disassembly of, or interference with, the relatively minute andotherwise numerous parts, such as the tumbler pins, springs, and thelike, while on thev other hand, the member 25 assures proper coactionbetween the cylindrical housing portion I5 of the casing, the connectingbar itself, and the rear end of the key plug.

More specifically, there is formed in the front plate I4 a slot orguideway 26 (Figures 2 and 3) whose width, as viewed in Figure 2,preferably is somewhat greater than the diameter of the fro-nt orflanged (IQ-20) end of the key plug I8 and Whose depth or verticaldimension is preferably Such that it extends from the peripheral face ofthe front plate I4 downwardly preferably toabout the axis of thecounterbore 22, thereby intersecting the counterbore. Into this slot 26,which may be cast or otherwise formed, is snugly and slidably fitted theabove-mentioned plate member 25, the latter being made preferably ofhardened steel or other suitable hard metal capable adequately to resistthe action of a tool such as a drill, or the like. The plate 25, shapedas is better shown in Figure 2, has its lower edge 25a cut or shaped ona curve whose radius is the same as the radius of curvature of thebottom of the annular groove 22 (Figure l) between the shoulders L11-20of the key plug I8, annular groove 22, plate 25, and plate-receivingslot 26,

being of substantially the same thickness or di- 4 mension (as seen inFigure 1) so that the lower edge portions of the plate 25 ride into theannular groove 2I with sumcient snugness to prevent movement in an axialdirection of the key plug I8 while permitting freedom of rotation of thelatter, and the plate 25 being received within the slot 26 withsufficient snugness to prevent play of the plate 25 relative to thecasing I3. Thus, the key plug I8 is dependably held in assembledrelation to the casing I3 and the above-mentioned alinement of therespective tumbler recesses and tumblers dependably maintained.

Thevertical or side edges of the slot 26, as seen in Figure 2, arepreferably parallel and equidistantly spaced from a vertical line drawnthrough the axis of the key plug I8 in which case the plate 25 will beseen to be symmetrical. Though plate 25 is received within the slot 26with sufficient snugness or tightness of ft, so as to be securely heldtherein by frictional contact with the walls of the slot, nevertheless,I prefer to lock the plate 25 in position and for that purpose I mayemploy a screw 21 (Figures 1, 4 and 3) threaded into and through thatportion of the front plate I4 that is to the rear of the slot 26 sothat, by tightening up the screw 21 it clamps the plate 25 betweenitself and the front wall portion of the slot 26 itself. In thatposition and because of the hardness of the material of the plate 25,the latter gives a protection to the lock mechanism that is of greatpractical importance. The expanse of the plate 25 both Vvertically andhorizontally (see Figure 2) is such as to form a substantial barrieragainst access, as by drilling through the front plate lll, to the`tumbler-receiving housing portion I6, and thus it becomes impossible todrill into the housing I5 in order thereby to drill away or dislodge thetuinblers 5|, 52, etc., and thereby endeavor to achieve rotation of thekey plug I8.

With the fixing of the rotatable key plug i8 in position within thecasing I3, as above described, there has simultaneously been broughtaboutalso a fixing of the interconnection of the connecting bar 28,which extends to the left into operative engagement with the boltmechanism Ik) (Figure 1), to the left or rear end of the key plug i8.The connecting bar 28, conveniently in the form of a. stamping of heavysheet metal, is substantially T-shaped, as is better shown in Figure 5,having at its end transversely projecting lugs 28a and 28h, the latter,however, being bent in opposite directions out of the plane of the bar28 itself, as is better shown in Figure' 6, giving the bar 28,therefore, an effective T-shape, either as viewed in Figure 5 or as seenfrom the top in Figure 5, the left or rear end of the key plug I8 isprovided with a T-slot I8"L (see Figures 8 and 7) open-ended at bothends, and into the T-slot ite the connecting bar 28 is slid, the throatof the T-slot being of a width substantially equal to the thickness ofthe connecting bar 28, the oppositely curved ears or lugs 28a-J8b of theconnecting bar being thereby made to extend into the wider or baseportion of the T-slot |8e, the connecting bar 28 being thusnon-rotatably connected to the key plug I8 and also held againstseparation therefrom by movement in the direction of the axis of the keyplug I8 itself. But the opposite open ends of the T-slot |8e,terminating as above mentioned in the peripheral or cylindrical face ofthe key plug, are now closed (see Figure 8) by the cylindrical portion|5 of the casing I3, so that movement of the connecting bar 28 along theT-slot |821, thus to disengage the bar from the key plug, is prevented.

It frequently happens, however, in practice, because of Variations intype or construction of the bolt or latch mechanism lil (Figure l) thatthe relation of the operating or connecting bar 28 to the key plug I8has to be changed. For example, assuming that the key plug I8 and thecasing I3 have the normal or locked positions shown in Figure l, thebolt mechanism It) may be of a type or kind or may be so positioned thatthe plate of the connecting bar 28 has to be vertical while, on theother hand, due to such factors as above-mentioned, the mechanism l!)may be of a type that requires the plane of the connecting bar 28 to behorizontal and hence displaced from what might be the requirement underother conditions or with another type of bolt mechanism |8. Or, stateddifferently, the slot in the roll-back or like device in the mechanisml0, depending upon the position cf the latter, the type or constructionof the latter, and other factors, and which slot is to receive theconnecting bar 28, extends either vertically or horizontally, and thekey-controlled mechanism must be made to meet these possible conditionswithout necessitating the impracticable rotating of the entire casing I3through 90.

Accordingly, I provide for meeting this peculiar condition and hence,referring now to Figure 4, I provide another T-slot |8b in the rear endof the key plug I8, T-slot |85, however, extending at right angles `andthus intersecting the abovementioned T-slot E821, as is clearly shown inFigure 4. Into either of these T-slots, therefore,

the operating bar 28 may be inserted, and in order to give access to theopen ends of the T- slots I8a and ith, without requiring disassembly ofthe key plug i8 from the casing I3 and' related parts, I provide in theupper rear portion of the housing portion I5 (see now Figures 3 and 4)and immediately1 to the rear or left of vthe tumbler housing portion I6,a slot |5ab whose peripheral extent or dimension is preferablyatleast-equal to the largest cross-sectional dimension of the T-slot |53aor |811.

Extending about this left or rear end of thecylindrical housing portionI5 and thus intersecting the slot l5a is an external peripherallyextending groove It?b (Figures 3 and 4) and in this-external peripheralgroove Ib is seateda split ring 29 made of a spring wire tending tocontact and hence acting always to grip the cylindrical housing portionI5. As is betterr` -shown in Figure 4, adjacent one end of the splitring 29, the latter is provided with an inwardly directed U-shaped bend28a suitably dimensioned to snugly fit into the slot HSE (see Figures 3and 4) and substantially fill the gap caused by vsaid slot |5a, atleastv in so far as the slot l5@ permits vmovement in a radial directionoftheconnecting bar 28 along a T-slot |8a or |81. Accordingly, theportion 29a of the split spring ring 29 substantially closes the slo-tI5'di and thus,

with the remaining portions of the cylindrical groove Iiib but to theleft of the slot |523 the latter being thereby exposed through the gapbetween the ends of the split ring 29. l

The key plug IS is thereupon rotated, with the aid to a key, of course,where necessary, to bring one end of the T-slot Ita in line with theslot |521, whereupon the connecting bar t8 may be slid upwardly, asviewed in Figure 4, out of the T-slot 8a and through the slot l 5e, andthus disengaged from the key-controlled mechanism. Thereupon,

the key plug i8 is givenfa 90 rotation, thus to bringv the T-slot i8bwith one end thereof juxtaposed to the open slot Ia, whence theconnecting bar ,28 is now inserted through the slot I52L and into theT-slot 28h, the shank of the connecting bar 28 being snugly receivedbetween the narrower portions ofthe T-slot mb and the laterallyprojecting lugs 28a and 28h projecting into the wider portions of theT-slct |811, assuming a relation such as is shown in Figure '7, themechanical interrelation being lthe same as theretofore existed betweenthe connecting bar 28 and the T-slot 25a) The split ring 28 is thereuponmoved about the external groove 15b in clockwise direction, as viewed inFigure 4, whereupon the inwardly directed portion 28e thereof snaps intothe slot |52, thus closing the latter and thus again coacting with thecylindrical housing portion and as a part of the latter to ypreventdisplacement vin a radial direction of the connecting bar 28 relative tothe key plug.

In the course of these operations, it will be perceived that'theconnecting bar 28 has been shifted through an angle of relative to thekey plug I8 vand has thus been adapted to meet the changed requirementsor conditions met with in practice and illustratively set forth above.This change in interrelation between the operating bar and the key plugwill be seen to be possible of achievement without having to remove thekey plug from the casing I3.

However, there may be and generally are conditions in practice underwhich it is necessary or desirable to remove the key plug I8 from thecasing I3; for example, for purposes of repair, replacement, or changeof parts, particularly of the tumblers, or even for purposes of fittinga new key. In such case, the casing I3 having been removed from the doorthe set screw 2'| (Figures 1, 3 and 4) is loosened up and the combinedarmor and locking plate 25 suciently Withdrawn relative to its slot 26to disengage it from the annular groove 2| (Figure 1) in the key plugI8. To facilitate such withdrawal, I cut away, as at |411 (Figures 3and 1) the rear wall of the slot 26, preferably in line with thetumbler-receiving housing portion I6, thus to expose an upper portion ofthe rear face of the plate 25. At such exposed portion of the plate 25 Iprovide in the latter a hole 25b (Figures 1 and 2) into which a suitableimplement may be inserted to raise the plate 25 against the friction ofits engagement with the slot 26.

It will be noted, however, that, Where it is necessary to attach ordetach the connecting bar 28, or to shift or change its relation to thekey plug or to the bolt mechanism IIJ, such operation or operations maybe quickly and speedily performed without having to disturby therelation of the key plug, casing, tumbler, tumbler recesses, springs,and like parts, the plate member 25 dependably holding the latteragainst disarrangement or disassembly. Entire freedom of action ormanipulation with respect to the connection of the connecting bar to thekey plug is thus permitted.

A preferred construction, however, for achieving such results as areabove pointed out and for achieving coaction with the armor plate member25, some of which coactions are above indicated, I have shown in Figures9-15 inclusive, in which, referring now to Figures 9, 10 and 11, thecasing and key plug construction and tumbler arrangement, including thefeature of the plate member 25, are substantially the same as describedin detail above in connection with Figures 1, 2, 3, 4 and 8, and theseparts, in Figures 9, 10 and 11, need not, therefore, be described indetail, excepting for certain features pointed out later herein. It willtherefore be noted that the casing I3 (Figures 9, 10 and 11) again hasthe front disk-like plate slotted as above described to receive thearmor plate member 25, the latter being capable of being locked inposition by the screw 21, and coacting with the annular groove formedbetween the annular or ring-like shoulders Ill-20 in the front end ofthe key plug I8. 'Ihe casin'g I3 again has the lower cylindrical housingportion I5 which is bored out rotatably to receive the key plug I8 andextending upwardly therefrom is the tumbier-receiving housing portionI6, containing the tumblers for coaction with the key plug tumblers vand key, as above described. The rearward (to- Ward the left) extensionof the cylindrical housshown in Figure 11, this rearward extension of10y the housing portion I5 is upwardly extended .as at I5g and forgreater compactness Vand convenience the lugs or ears |38 and |39 extendrespectively to the left and right of this upward extension |51, asseenin Figure 11. l5I A With the added metal thus provided by the`portion I5?, I am enabled to provide therein a slot |511 (Figures 9 and10) extending transversely of the bore I1 in which the key plug I8 isrotatably mounted, slot |511 having a width, 2()- as viewed in Figure1l, substantially equal to the diameter of the bore all for a purposeabout to be described.

The left or rear end of the key plug I8V is provided with two slots I8gand |811 (Figures 11 and 25 i I2), extending at right angles to eachother and as will be later more apparent, these slots need not beundercut and thus lend themselves to less expensive manufacture,simplifying the casting, or milling operations. slot |811 extends in theplane of the key slot23 in the key plug I8, just as the slot |81L of thekey plug of Figure 8 extends in the plane of the key slot 23, all asabove described.

The connecting bar preferably takes the form 35..

better shown in Figures 13 and 14, the connecting bar 28 there shownbeing substantially T- shaped, having end lugs |2811 and |28b which, asis better shown in Figure 14, can be and preferably are in the plane ofthe connecting bar |28 40 itself; that need not be bent out of thatplane as was the case with the illustrative form shown in Figures 5 and6 and above described.

The right-hand end of the connecting bar |28,

as viewed in Figure 13, is receivable in either of 45 I the slots |88 or|811 in the rear end of the key plug |8, for reasons above alreadydescribed in some detail, and in Figures 10 and 11 that end ofconnecting bar |28 is shown received within slot |811. 50

With the plate member 25 fixing the position of key plug 8, as abovedescribed, the plane of the bottoms of the end slots |81? and 811 in thekey plug I8 (seenow Figure 10) is in line with the right-hand wall of aslot I5j (see also Figure 55 9) that is cut in the casing or extensionportion I5g from the upper edge thereof right down into the bore I1,slot |51' connecting at its left-hand end (see Figures 9 and 10) withthe transverse slot |511. Where slot I5j extends to the right or 60,forwardly of the transverse slot |511, I provide a slot |5k in theextension portion |511 to the left or rearwardly of transverse slot |511(see Figures 9, 10 and 1.1), slot 511 extending from the top edge of theextension portion I5g right down into' 65 the bore and also connectingwith the transverse slot |511 (Figure 9). Accordingly, with either slot|8lg or |811 extending vertically, a position achieved by rotating thekey plug I8, as

viewed in Figure 11, that slot of the two which 70 is thus made toextend vertically, illustratively slot |811 (Figures 10 and 1l) is thusbrought into alinement with the vertical slots I5k and |5j abovedescribed, these two slots being intersected by the transverse slot|511, and accordingly con- 5 One of the slots, such as 30 necting bar|28 may be slid in the direction of its own plane (vertically, as viewedin Figure 10) through the slots l5k and |51' and thus into the plug slot|811, much in the same manner as the connecting bar 28 of Figures 2 8may be related to a transverse slot in the key plug when the cylindricalcasing portion is opened up as at the slot I5a (Figure 3) therein uponmoving the ring member 29 out oit slot-closing position.

The composite slot ihk-|51' of` Figures 9, 10 and 11, thus transverselyopening up the cylindrical housing portion I5, I also provide to beclosed or opened at will; for this purpose I employ a plate-like member|29 (see now Figure 15) shaped to be snugly fitted and received into thetransverse slot I5h (Figures 9 and l1); the plate member |29 accordinglyhas parallel side edges adapted to mate with the parallel and verticallyextending sides, as viewed in Figure 11, of the transverse slot |51,joined by a lower arcuate edge |2921 shaped or curved so as to snuglybottom in, or mate with the curvature of, the bore (see Figure 1l) andwhen thus bottoming in the bore i'i, the upper horizontal edge of theplate member |29 preferably mates with the upper horizontal edge of theextension portion I5g (Figure ll) of the housing. Now plate member |29is virtually in the form o1" a ring, having an opening therein |29b of adiameter slightly in excess of the width of the connecting bar |28(Figure 13) so that the latter may pass therethrough and be freelyrotated relative thereto, but lugs I28e|2ilb (Figure 13) preventing thecomplete passage through the ring member |29 of the connecting bar |28.

Accordingly, when sliding the connecting bar |28 downwardly (Figure 10)through the composite slot ISL-iw, and the ring or plate member |29having first been slipped onto the connecting bar |28, the member |29moves downwardly into its slot I51fl as the connecting bar |28 passesdownwardly through the slots I5k-I5g, emerges from the latter, and seatsthe head end, with lugs lifes-IEM, into plug slot Ih, resulting in arelation of the parts as is better shown in Figures 9, 19 and ll.

Withdrawal or the operating bar |28 in a direction toward the left, asseen in Figure 10, is precluded by the plate member |29, whose aperture|29b does not permit the passage therethrough of the lugs @9L-|291).With the plate member 25 preventing the key plug i8 from moving towardthe right, as viewed in Figures 9 and 10, and with the member |29preventing movement of the connecting bar |28 toward the left, as viewedin these figures, the telescopic connection between key plug I8 andconnecting bar |28, the latter tting into the slot I8h (or I8g, as thecase may be), is dependably and eectively maintained, and hence therotation of the connecting bar |28 with consequent actuation of the boltmechanism I9 (Figure 1) in response to rotation of the key plug i8 underthe control of a, key must follow.

Referring again to Figure l5, the lower portion of member |29 isprovided with a lug or tab |29c which, referring now to Figures lO andl1, is received within a slot I5m in the lower end of the cylindricalcasing portion i5, slot l5m being, of course, in alineinent with thetransverse slot l5h and thus dependably anchoring the lower end of themember |29.

Preferably the member |29 is relatively snugly or tightly fitted intoits slot |51, or I5m, or both, so that it will be held within the slotby the frictional gripping action of the walls of the latter; it may be,for example, in the nature of a tapt as distinguished from a force-fit.And to facilitate withdrawal of the member |29 from its slot withouthaving to subject the connecting bar 4 |28 to any strain or stress, Iprovide in the member |29 an aperture |29e positioned so that, when themember |29 is within its slots h-I 5m, aperture |29e is in alinementwith the vertical slot I5k (see Figure 11) the aperture being thusaccessible from the rear of the casing i3. Accordingly, any suitableinstrument may be inserted through the slot |5k into the aperture |29eand member |29, and the latter withdrawn by such instrument againstwhatever forces hold the member in its slot.

Should such withdrawal of the holding member |29 be effected, platemember 25 (Figures 9 and 10) holds the key plug I8 against removal fromthe casing i3, and thus precludes spilling of the tumblers, springs, orlike small parts. Replacement of the connecting bar which, it is to benoted, is disconnected from the key plug and casing at the same timethat the member |29 is withdrawn as above described, is a simpleoperation, requiring only a reverse of what has just been described, andif it is necessary that the relation between connecting bar |28 and thekey plug I8 be shifted the replacement of the connecting bar |28 is madeafter key plug I8 has been given a 90 turn, as with the key, to bringthe other slot, illustratively slot I8g (Figure ll) in alinement withthe composite vertical slot I5k|5j (Figure 19).

Once the connecting bar |28 is thus inserted into an end slot in the keyplug and the member |29 returned to its slots I5h|5m so as again to forma p-art of or to restore the cylindrical housing portion I5, the latter,now having its composite transverse slot |5k--I5j closed, effectivelyprevents the connecting bar |28 from riding, in a transverse direction,out of whichever of the various slots in the plug I8 that it is seatedin. Moreover, just as was the case with the construction above describedin connection with Figures 1-8 inclusive, any side or transverse thrustson or by the connecting bar, that is, in a radial direction relative tothe key plug, are dependably and reliably resisted by the wall of thebore in which the key plug is rotatably mounted, and thus disconnectionof the connecting bar from any plug by movement of the former along aradius (or slot) of the latter is reliably resisted by the wall of thebore to which such side or trans- Verse thrusts are transmitted.

As above indicated, the construction just described and shown in Figures9-14 inclusive, is in all respects other than those just mentioned, thesame as that set forth in connection with Figures l 1-8 inclusive.

The upper edge 25c (Figure 2 or l1) of the plate 25 has a curvature thatmatches the curved periphery of the front plater I4 so that when theplate 35 is in operative or downward position, the plate 25 does notproject from the periphery of the front plate Ill. Moreover, theconstruction, when installed, as illustrated in Figure l, is such thatthe upper end of the slot 25, and hence also the upper edge 25c of theplate 25, are concealed and inaccessible inasmuch as the front plate I4is snugly received within a suitably stepped or ilanged ring 39(Figure 1) which covers over the periphery of the front plate i4, and,moreover, has portions that extend to the rear of the latter, suchportions of ring 38 resting against the righthand face of the door Il,as shown in Figure 1,

and not being removable from the front or righthand side of the door II.

This because of the intertting relation between the ring 3E) and thefront plate I4 and also the manner of securing the casing I3 in the holeI2 in the door II. In effect, the door II and the ring 39 are securelyclamped between a back plate 36 (Figure l) that rests against the inneror lefthand face of the door II, extending underneath the casing of thelock mechanism I0, and the front plate I4 of the casing I3; thisclamping is achieved by means of screws 37 that pass through the backplate 3B, excepting for their heads, and they are threaded into threadedopenings in the ears 38 and 39 (Figure 3 and 4) integrally formed withthe left or rear portion of the casing I3. A suitable hole in the backplate 36 permits the passage therethrough of the connecting bar 28 as itextends toward the left (Figure l) into the slot of the roll-back orother device by which the bolt mechanism Ii) is actuated.

Thus, it will be seen that there has been pro'- vided in this inventiona lock construction in which the various objects hereinbefore set forth,together with many thoroughly practical advantages, are successfullyachieved. It will be seen that the construction is of a thoroughlypractical nature, is inexpensive, is timeand laborsaving in assembly ordisassembly, and is of thoroughly dependable action in use. Moreover,also, dependable protection against drilling into vital parts of thekey-controlled mechanism is afforded in a thoroughly reliable and simplemanner and thus greater security achieved. Moreover, the construction iscompact and neat and particularly as to the casing and key plug lendsitself readily to casting, particularly die casting.

As many possible embodiments may be made of the above invention and asmany changes might vbe made in the embodiment above set forth, it is tobe understood that all matter hereinbefore set forth or shown in theaccompanying drawings is tol be interpreted as illustrative and not in alimiting sense.

l. In lock construction, in combination, a casing having an open-endedcylinder portion containing a bore, a key plug having a key slot androtatably fitted into said bore, tumbler means controllable by a keyinserted into said key slot for coaction with said key plug and casing,an operating bar, means forming a detachable interconnection betweensaid operating bar and the rear end of said key plug and capable ofdisconnection only upon moving said connecting bar in the direction of aradius of said key plug, and means releasably holding said key plugagainst movement in an axial direction to maintain the key plug andtumbler means and casing in proper alinement and to cause a Wall of saidbore to prevent movement in a radial direction of said operating bar andthus maintain interconnection thereof with said key plug.

2. In lock construction, in combination, a casing having an open-endedcylinder portion containing a bore, a key plug having a key slot androtatably fitted into said bore, tumbler means controllable by a keyinserted into said key slot for coaction with said key plug and casing,an operating bar, means forming a detachable interconnection betweensaid operating bar and the rear end of said key plug and capable ofdisconnection upon moving sai-d connecting bar in the direction of aradius of said key plug, said key plug having a groove extending in thedirection of its periphamigar vent axial displacement of said key plugand thereby to hold said connecting bar and said plug againstdisconnection.

3. In lock construction, in combination, a casing having an open-endedcylinder portion containing a bore, a key plug having a key slot androtatably fitted into said bore, tumblerV means controllable by a keyinserted into said key slot for coaction with said key plug and casing,an operating bar, means forming a detachable interconnection betweensaid operating bar and the rear end of sai-d key plug and capable ofdisconnection upon moving said connecting bar in the direction of aradius of said key plug, said keyk plug having a peripheral grooveadjacent its forward end and said casing having a slot in the front wallthereof, said slot extending in a direction transversely to the axis ofthe key plug and opening into said bore, and a plate-like member ofrelatively hard metal fitted into said last-mentioned slot and engaginginto the peripheral groove in said key plug, thereby to hold the latteragainst axial displacement and in a position to cause a wall of saidbore to prevent movement in a radial direction of said connecting barrelative to the plug.

4. In lock construction, in combination, a casing having an open-endedcylinder portion containing a bore, a key plug having a key slot androtatably tted into said bore, tumbler means controllable by a keyinserted into said key slot for coaction with said key plug and casing,an operating bar, means forming a detachable interconnection betweensaid operating bar and the rear end of said key plug and capable ofdisconnection upon moving said connecting bar in the direction of aradius of said key plug, said key plug having a peripheral grooveadjacent its forward end and said casing having a slot in the front wallthereof, said slot extending in a direotion transversely to the axis ofthe key plug and opening into said bore, and a plate-like member ofrelatively hard metal fitted into said lastmentioned slo-t and engaginginto the peripheral groove in said key plug, thereby to hold the latteragainst axial displacement and in a position to cause a wall of saidbore to prevent movement in a radial direction of said connecting barrelative tothe plug, said last-mentioned slot and hence the platereceived therein having a width equal to or greater than the width ofthat portion of said casing with which said tumbler means coacts,thereby to prevent a tool like a drill from passage therethrough andinto said portion of said casing.

5. In lock construction, in combination, a casing having an open-endedcylinder portion containing a bore, a key plug having a key slot androtatably tted into said bore, tumbler means controllable by a keyinserted into said key slot for coaction with said key plug and casing,an operating bar, means forming a detachable interconnection betweensaid operating bar and the rear end of said key plug and capable ofdisconnection upon moving said connecting bar in the direction of aradius of said key plug, said key plug having a peripheral grooveadjacent its forward end and said casing having a slot in the front wallthereof, said slot extending in a direction transversely to the axis ofthe key plug and opening into said bore, and a plate-like mem- CFI berof relatively lhard metal tted into saidlastmentioned slot and engaginginto the peripheral groove in said key plug, thereby to hold the latteragainst axial displacement and in a position to cause a wall of saidbore to prevent movement in a radial direction of said connecting barrelative to the plug, and releasable means accessible from a face ofsaid casing other than the front face thereof for locking said plateagainst withdrawing movement relative to its slot.

6. In lock construction, in combination, a casing having an open-endedcylinder portion containing a bore, a key plug having a key slot androtatably fitted into said bore, tumbler means controllable by a keyinserted into said key slot for coaction with said key plug and casing,an operating bar, means forming a detachable interconnection betweensaid operating bar and the rear end of sai-d key plug and capable ofdisconnection upon moving said connecting bar in the direction of aradius of said key plug, said key plug having a peripheral grooveadjacent its forward end and said casing having a slot in the front wallthereof, said slot extending in a direction transversely to the axis cithe key plug and opening into said bore, and a plate-like member ofrelatively hard metal fitted into said last-mentioned slot and engaginginto the peripheral groove in said key plug, thereby to hold the latteragainst axial displacement and in a position to cause a wall of saidbore to prevent movement in a radial direction of said connecting barrelative to the plug, and a screw threaded through a wall of saidlast-mentioned slot other than the front wall thereof for engagementwith said plate and for locking the latter against withdrawing movementrelative to its slot.

7. In lock construction, in combination, a casing having an open-endedcylinder portion containing a bore, a key plug having a key slot androtatably tted into said bore, tumbler means controllable by a keyinserted into said key slot for coaction with said key plug and casing,an operating bar, means forming a detachable interconnection betweensaid operating bar and the rear endof said key plug and capable ofdisconnection upon moving said connecting bar in the direction of aradius of said key plug, said key plug having a peripheral grooveadjacent its forward end and said casing having a slot in the front Wallthereof, said slot extending in a direction transversely to the axis ofthe key plug and opening into said bore, and a plate-like member ofrelatively hard metal iitted into said lastmentioned slot and engaginginto the peripheral groove in said key plug, thereby to hold the latteragainst axial displacement and in a position to cause a wall of saidbore to prevent movement in a radial direction of said connecting barrelative to the plug, and means for closing the open end of saidsecond-mentioned slot.

8. In lock construction, in combination, a casing having an open-endedcylinder portion containing a bore, a key plug having a key slot androtatably fitted into said bore, tumbler means controllable by a keyinserted into said key slot for coaction with said key plug and casing,an operating bar, means forming a detachable interconnection betweensaid operating bar and the rear end of said key plug and capable ofdisconnection upon moving said connecting bar in the direction of aradius of said key plug, said key lplug having a peripheral grooveadjacent its forward end and said casing having a slot in the front wallthereof, said slot extending in a direction transversely to the axis ofthekey plug and opening into said bore, and a plate-like member ofrelatively hard metal tted into said lastmentioned slot and engaginginto the peripheral groove in said key plug, thereby to hold the latteragainst axial displacement and in a position to cause a wall of saidbore to prevent movement in a radial direction of said connecting barrelative to the plug, and means interlocked With said front Wall whenthe mechanism is installed for closing the open end of saidlast-mentioned slot.

9. In lock construction, in combination, a casing having an open-endedcylinder portion containing a bore, a key plug having a key slot androtatably fitted into said bore, tumbler means controllable by a keyinserted into said key slot for coaction with said key plug and casing,an operating bar, means forming a detachable interconnection betweensaid operating bar and the rear end of said key plug and capable ofdisconnection upon moving said connecting bar in the direction of aradius of said key plug, said key plug having a peripheral grooveadjacent its forward end and said casing having a slot in the iront wallthereof, said slot extending in a direction transversely to the axis ofthe key plug and opening into said bore, and means mounted in saidsecond-mentioned slot and engaging into the peripheral groove in saidkey plug for holding the latter against axial displacement and in aposition to cause a wall of said bore to block movement of saidoperating bar in a radial direction relative to said key plug.

l0. In lock construction, in combination, a casing having an open-endedcylinder portion containing a bore, a key plug having a key slot androtatably tted into said bore, the rear end of said key plug having atransversely extending undercut slot open at a side of said key plugaconnecting bar having an end portion shaped to move into said slot uponmovement of said bar in the direction of the radius of said plug,thereby to interlock with said plug, and means for holding said plugagainst axial displacement relative to said casing and in such aposition relative to the latter that a wall of said bore closes off theopen end of said undercut slot.

il. In lock construction, in combination, a casing having an open-endedcylinder portion containing a bore, a key plug having a key slot androtatably iitted into said bore, the rear end of said key plug having aplurality of undercut slots therein extending at an angle to each otherand each opening in the periphery of said plug, the wall of said borehaving an axial extent suiiicient to encompass the portions of the plugin which said slots open, the wall oi said bore having a portion cutaway thereby to expose, upon appropriate rotation of said plug, the openend of a slot, a connecting bar having an end portion shaped to pass'through said cut away portion of said bore wall and to interlock withan undercut slot alined with said cut away portion, thereby to becomeinterlocked with said key plug, and releasable means for closing offsaid cut away portion of said bore wall.

12. In lock construction, in combination, a casing having an open-endedcylinder portion containing a bore, a key plug having a key slot androtatably fitted into said bore, the rear end of said key plug having aplurality of undercut slots therein extending at an angle to each otherand each opening in the periphery of said plug, the wall of said borehaving an axial extent suicient to encompass the portions of 'the plugin which saidslots open, the wall of said bore having a portion cutawaythereby to expose, upon appropriate rotation of said plug, the open endof a slot, a connecting bar having an end portion shaped to pass throughsaid cut away portion of said bore wall and to interlock with anundercut slot alined with said cut away portion, thereby to becomeinterlocked with said key plug, and spring-mounted means yieldablymovable into or out of the cut away portion of the wall of said bore.

13. In lock construction, in combination, a casing having an open-endedcylinder portion containing a bore, a key plug having a key slot androtatably fitted into said bore, the rear end of said key plug having aplurality of undercut slots therein extending at an angle to each otherand each opening in the periphery of said plug, the wall of said borehaving an axial extent sufficient to encompass the portions of the plugin which said slots open, the wall of said bore having a portion cutaway thereby to expose, upon appropriate rotation of said plug, the openend of a slot, a connecting bar having an end portion shaped to passthrough said cut away portion of said bore Wall and to interlock with anundercut slot alined with said cut away portion, thereby to becomeinterlocked with said key plug, and a ring-like member rotatably engagedwith the exterior of said bore wall having a portion that may be moved,upon rotation relative to said bore wall, into a position to close thecut away portion of the latter or into a position to expose saidportion.

14. In lock construction, in combination, a casing having an open-endedcylinder portion containing a bore, a key plug having a key slot androtatably iitted into said bore, the rear end of said key plug having aplurality of undercut slots therein extending at an angle to each otherand each opening in the periphery of said plug, the wall of said borehaving an axial extent suiiicient to encompass the portions of the plugin which said slots open, the wall of said bore having a portion cutaway, thereby to expose, upon appropriate rotation of said plug, theopen end of a slot, a connecting bar having an end portion shaped topass through said cut away portion of said bore wall and to interlockwith an undercut slot alined with said cut away portion, thereby tobecome interlocked with said key plug, and a split spring ring grippingthe exterior of the Wall of ysaid bore and movable relative to thelatter to close or to expose the cut away portion therein.

15. In lock construction, in combination, a casing having an open-endedcylinder portion containing a bore, a key plug having a key slot androtatably fitted into said bore, the rear end of said Akey plug having aplurality of undercut slots therein extending at an angle to each otherand each opening in the periphery of said plug, the wall of said borehaving an axial extent sufficient to encompass the portions of the plugin which said slots open, the wall of said bore having a portion cutawaythereby to expose, upon appropriate rotation of said plug, the open endof a slot, a connecting bar having an end portion shaped to pass throughsaid cut away portion of said bore wall and to interlock with anundercut slot alined with said cut away portion, thereby to becomeinterlocked with said key plug, the exterior of the wall of said borehaving a peripheral groove intersecting the cut away portion thereof,an-d a split spring ring rotatably mounted in said groove and having aninwardly directed portion normally seated in the out away portion ofsaid wall.

16, In lock construction, in combination, a casing having an open-endedcylinder portion con# taining a bore, a key plug having .a key slot androtatably fitted into said bore, the rear end of said key plug having aplurality of lundercut slots therein extending at an angle to each otherand each opening in the periphery of said plug, the wall of said borehaving an axial extent sulicient to encompass the portions of the plugin which said slots open, the wall of said bore having a portion cutaway thereby to expose, upon appropriate rotation of said plug, the openend of a slot, a connecting bar having an end portion shaped to passthrough said cut away portion of said bore wall and to interlock with anundercut slot alined with said cut away portion, thereby, to becomeinterlocked with said key plug, the exterior of the wall of said borehaving a peripheral groove intersecting the cut away portionthereof, andmeans having a gap therein and rotatably carried in said groove adaptedupon rotary movement thereof to register said gap with said cut awayportion or to move it out of registry therewith.

17. In lock construction, in combination, a. casing having an open-endedcylinder portion containing a bore, a key plug having a key slot androtatably fitted into said bore, the rear end of said key plug having atransversely extending slot open at a side of said key plug, aconnecting bar having an end portion that may be moved into saidtransverse slot upon movement of said bar in the direction of a radiusof said plug, and means for holding said plug against axial displacementrelative to said casing and in such a. position relative to the latterthat a wall of said bore closes ofi the open end of said transverseslot.

18. In lock construction, in combination, a oasing having an open-endedcylinder portion containing a bore, a key plug having a key slot androtatably tted into said bore, the rear end of said key plughaving atransversely extending slot open at a side of said key plug, saidcylinder `portion having a slot in the wall of the bore thereof withwhich the open end of said transverse slot may be made to register uponappropriate rotation of the key plug, a connecting bar having an endportion shaped to pass through said third-mentioned slot and into saidtransverse slot upon said two slots being brought into registry, therebynon-rotatably to interconnect said connecting bar and said key plug, andmeans mounted and carried by said casing for holding said connecting baragainst movement out of the open end of said transverse slot if thelatter sub- -sequently is brought into registry with saidthird-mentioned slot.

19. In lock construction, in combination, a casing having an open-endedcylinder portion containing a bore, a key plug having a key slot androtatably tted into said bore, the rear end of said key plug having atransversely extending slot open at a side of said key plug, saidcylinder portion having a slot in the wall of the bore thereof withwhich the open end of said transverse slot may be made to register uponappropriate rotation of the key plug, a connecting bar having an endportion shaped to pass through said third-mentioned slot and into saidtransverse slot upon said two slots being brought into registry, therebynon-rotatably to interconnect said connecting bar and said key plug, andmeans carried by said casing for holding said connecting bar and saidkey plug against relative movement in an axial direction.

20. In lock construction, in combination, a casing having an open-endedcylinder portion containing a bore, a key plug having a key slot androtatably fitted into said bore, the rear end of saidv key plug having atransversely extending slot open at a side of said key plug, saidcylinder` portion having a slot in the wall of the bore thereof withwhich the open end of said transverse slot may be made to register uponappropriate rotation of the key plug, a connecting bar having an endportion shaped to pass through said third-mentioned slot and into saidtransverse slot upon said two slots being brought into registry, therebynon-rotatably to interconnect said connecting bar and said key plug, anda member insertable into said third-mentioned slot for preventingmovement of said connecting bar out of said transverse slot.

21. In lock construction, in combination, a casing having an open-endedcylinder portion containing a bore, a key plug having a key slot androtatably fitted into said bore, the rear end of said key plug having aplurality of slots therein extending at an angle to each other and eachopening in the periphery of said plug, the wall of said bore having anaxial extent sufficient to encompass the portions of the plug in whichsaid slots open, the wall of said bore having a portion cut away therebyto expose, upon appropriate rotation or said plug, the open end of aslot, a connecting bar having an end portion shaped to pass through saidcut away portion of said bore wall and to enter a slot exposed to saidcut away portion, thereby to become non-rotatably connected with saidkey plug, and releasable means carried by said casing for holding saidconnecting bar against movement out of the slot in which it has beenentered.

22. In lock construction, in combination, a casing having an open-endedcylinder portion containing a bore, a key plug having a key slot androtatably fitted into said bore, the rear end of said key plug having aplurality of slots therein extending at an angle to each other and eachopening in the periphery of said plug, the Wall of said bore having anaxial extent sullcient to encompass the portions of the plug in whichsaid slots open, the wall of said bore having a portion cut away therebyto expose, upon appropriate rotation of said plug, the open end of aslot, a connecting bar having an end portion shaped to pass through saidcut away portion of said bore wall and to enter a. slot exposed to saidcut away portion, thereby to become] non-rotatably connected with saidkey plug, said end portion of the connecting bar having a greatertransverse dimension than the remainder of -the connecting bar, saidcylinder portion of the casing having a slot extending transversely ofand to the rear of the rear end of said key plug, and a member having anaperture therein through which said remainder of the connecting barextends but through which said end portion thereof cannot pass seated insaid transverse slot and movable into or out of the latter in the samedirection in which said connecting bar is movable into or out of a plugslot when the latter is exposed through said cut away portion of thewall of said bore.

23. In lock construction, in combination, a casing having an open-endedcylinder portion containing a bore, a key plug having a key slot androtatably iitted into said bore, the rear end of said key plug having aplurality of slots therein extending at angle to each other and eachopening in the periphery of said plug, the wall of said bore said plug,the open end of a slot, a connecting bar 5 having an end portion shapedto pass through said cut away portion of said bore wall and to enter aslot exposed to said cut away portion, thereby to become non-rotatablyconnected with said key plug, said end portion of the connect- 10 l ingbar having a greater transverse dimension than the remainder of theconnecting bar, and means coacting with said end portion for preventingmovement in an axial direction of the connecting bar out of the slot inwhich it has 15 been entered.

24. In lo-ck construction, in combination, a casing having an open-endedcylinder portion containing a bore, a key plug having a key slot androtatably tted into said bore, tumbler means-.20 controllable by a keyinserted into said key slot for coaction with said key plug and casing,an operating bar, means forming a detachable interconnection betweensaid operating bar and the rear end of said key plug and capable ofdiscon- 25 nection upon moving said connecting bar in the direction of aradius ci said key plug, said detachable interconnection means includingmeans for preventing movement of said connecting bar away from said keyplug in the direction of the 30 axis of the latter and said key plughaving a groove extending in the direction of its periphery and saidplug normally having such a positio-n that a wall of said bore resistsmovement of said connecting bar along a radius of said key 35 plug, andmeans projecting from said casing into said groove to prevent axialdisplacement of said key plug.\

25. In lock construction, in combination, a casing having a bore forrotatably receiving therein 40 a key plug and having a iront end wallthat is circular, there being a casing portion extending rearwardly ofsaid front end wall for receiving tumbler means, said front end wallhaving a slot therein extending from the periphery thereof to 45 andinto communication with said bore and being of suiiicient lateralexpanse to extend in front of said tumbler portion of said casing, a keyplug rotatably received in said bore and having a peripheral grooveadjacent its forward end and 50 substantially alined with said slot, anda platelike member or" relatively hard metal tted into said slot andthereby extending across and in front of said tumbler portion of thecasing and extending into the peripheral groove of said key 55 plug,thereby to hold the latter against axial displacement, and meansinaccessible when said lock construction is installed for preventingwithdrawing movement of said plate-like member relative to its slot. 60

26. A lock construction as claimed in claim 25 in which the means forpreventing withdrawing movement of the plate-likey member comprises ascrew threaded through a wall of said slot other than the front walltherefor for blocking with- 65 drawing movement of said plate-likemember relative to its slot.

27. A lock construction as claimed in claim 25 in which the means forvpreventing withdrawing movement of the plate-like member comprises aflanged ring-like member receivable over said circular front end walland closing the outer end of said slot, a flange of said ring-likemember engaging to the rear of said front end wall.

28. In lock construction, in combination, a

Vinder portion having a slot in the wall of the bore said cylinderportion having a slot in the wall of the bore thereof with which theopen end of said transverse slot may be made to register uponappropriate rotation of the key plug, a connecting bar having an endportion shaped to pass .through said registered slots and to enter intothe transverse slot in the key plug, thereby to become non-rotatablyconnected with said key plug, said end portion of the connecting barhaving a greater transverse dimension than the remainder of theconnecting bar, and means carried by ysaid casing and projectableradially into said bore and to the rear of said greater-dimensioned endportion of the connecting bar, thereby to prevent disengagement of saidconnecting bar in an axial direction from said key plug.

" 29. In lock construction, in combination, a casing having a cylinderportion containing a bore, a key plug rotatably fitted into said bore,the rear end of said key plug having a transversely extending slot openat a side of said key plug, said cylthereof with which the open end ofsaid transverse slot may be made to register upon appropriate rotationof the key plug, a connecting bar having an end portion shaped to passthrough said registered slots and to enter into the transverse slot inthe key plug, thereby to become nonrotatably connected with said keyplug, said end portion of the connecting bar having a greater.transverse dimension than the remainder of the connecting bar, saidcasing having a recess adjacent its rear end communicating with saidbore, and a member encircling said connecting bar adjacent said endportion thereof and received into said recess as and when saidconnecting bar is inserted into said transverse plug slot upon registryof said two slots, for preventing disconnection of said connecting barfrom said key plug in an axial direction.

30. In lock construction, in combination, acasing having a cylinderportion containing a bore, a key plug rotatably fitted into said bore,the rear end of said key plug having a transversely extending slot openat a side of said key plug, said cylinder portion having a slot in thewall of the bore thereof with which the open end of said transverse slotmay be made to register upon appropriate rotation of the key plug, aconnecting bar having an end portion shaped to pass through saidregistered slots and to enter into the transverse slot in the key plug,thereby to become nonrotatably connected with said key plug, said endportion of the connecting bar having a greater transverse dimension thanthe remainder of the connecting bar, said cylinder portion having a slotadjacent its rear end and intersecting said bore rearwardly of the rearend of said key plug, and a plate-like member having an aperture thereinthrough which said remainder of the connecting bar extends but throughwhich said end portion 'thereof` cannot pass received in saidthird-mentioned slot and movable into or out of the latter concurrentlywith movement of said connecting bar, when said first two-mentionedslots are in registry, into or out of said key plug slot.

31. In lock construction, in combination, a casing having an open endedcylinder portion containing a bore, a key plug rotatably fitted intosaid bore, therear end of said key plug having a transversely extendingslot therein opening in the periphery of lsaid plug, the wall of saidbore having an axial extent sufficient to encompass the portions of saidplug in which said slot opens at the periphery and the wall of said borehaving a portion cut away thereby to expose, upon appropriate rotationof said plug, the open end of said slot, said slot being undercut, aconnecting bar having an end portion shaped to pass through said y cutaway portion of said bore wall and to enter said slot when the latter isexposed to said cutv away portion and to interiit with said undercutslot, thereby to become non-rotatably connected with said key plug andsaid connecting bar and portion of the wall of said bore, thereby topre- 2()A vent exposure of said slot and to prevent movement in radialdirection of said connecting bar.

32. In lock construction, in combination, a casing having an open endedcylinder portion containing a bore, a key plug rotatably tted into saidbore, the rearend of said key plug having a transversely extending slottherein opening in the periphery of said plug, the wall of said borehaving an axial extent suflicient to encompass the portions of said plugin which said slot opens at the periphery and the wall of said borehaving a portion cut away thereby to expose, upon appropriate rotationof said plug, the open end of said slot, said slot being undercut, `aconnecting bar having an end portion shaped to pass through said cutaway portion of said bore wall andto enter said slot when the latter isexposed to said cut away portion and to intert with said undercut slot,thereby to become non-rotatably connected with said key plug and saidconnecting bar and key plug being thereby incapable of disconnection,except through movement in radial direction of said connecting barthrough said cut away portion, and spring-mounted means yieldablymovable into or out of the cut away portion ofthe wall of said bore.

33. In lock construction, in combination, a casing having an open endedcylinder portion containing a bore, a key plug rotatably fitted intosaid bore, the rear end of said key plug having a transversely extendingslot therein opening in the periphery of said plug, the wall of saidbore having an axial extent suicient to encompass the portions of saidplug in which said slot opens at the periphery and the wall of said borehaving a portion cut away thereby to expose, upon appropriate rotationof said plug, the open end of said slot, and a connecting bar having aT-shapedend portion which is movable through said cut away portion andinto said plug slot, thereby to become HENRY F. KEIL.

